PHYSIOLOGY, AND PATHOLOGY OF THE CHIMPANZEE. 



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internal maxillary, superficial temporal, and transverse facial 

 arteries. The branches run in different directions. Coursing 

 mesially are the superior thyroid (S.T.A), a combined lingual 

 and external maxillary trunk (L.F.T), transverse facial and 

 internal maxillary arteries. Running laterally is the occipital 

 artery (O.A.), and vertically the superficial temporal, ascending 

 pharyngeal and parotid arteries. 



The superior thyroid artery (text-fig. 41, S.T.A) arises almost 

 at the beginning of the external carotid. It describes the usual 



Text-figure 41. 



L.F.T. 



The larynx, thyroid gland and vessels of the neck. H.B : hyoid bone; 0-H.M : 

 omo-liyoid muscle ; S-H.M : sterno-hyoid muscle; S.T.M : steruo-thyroid 

 muscle; T.G : thyroid gland; T.H.M : thyro-hyoid muscles; T-M.A: 

 temporo-maxillary artery; T-P.B : thymus and parathyroid; XII: hypo- 

 glossal nerve. Other letters in text. 



curve, with its convexity upwards, and then descends along the 

 greater part of the mesial border of the lateral thyroid lobe. It 

 terminates by anastomosing with the thyroidea ima (T.I. A). 

 It gives off mesial branches to the omo-hyoid, sterno-hyoid, 

 sterno-thyroid, crico-thyroid and thyro-hyoid muscles ; and a 

 bi'anch enters the larjaix thi'ough the thyro-hyoid interval. The 

 lateral branches supply the thyroid gland and anastomose with 

 branches of the middle thyroid artery. The corresponding 

 superior thyroid vein enters the anterior facial vein. The 



